Developer cartridge

Abstract

To provide a structure capable of suppressing the rubbing of an electric contact surface when a development cartridge is mounted.SOLUTION: A development cartridge 1 includes a housing 10 for accommodating a developer therein; a storage medium 61 having an electric contact surface 611; a holder 62 for holding the electric contact surface 611; and an elastic member 73. The elastic member 73 can be extended and contracted in a first direction between a first state and a second state more contracted than the first state. The outer surface which holds the electric contact surface 611 of the holder 62 is arranged at a first position when the elastic member 73 is in the first state, and is arranged at a second position when the elastic member 73 is in the second state. In this manner, the position of the outer surface of the holder 62 by which the electric contact surface 611 is held is changed in a first direction. As a result, when the development cartridge 1 is mounted, the rubbing of the electric contact surface 611 can be suppressed.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present invention relates to a developing cartridge. [Background technology]

[0002] Conventionally, electrophotographic image forming devices such as laser printers and LED printers are known. A developing cartridge is used in the image forming device. The developing cartridge has a developing roller for supplying toner. The developing cartridge described in Patent Document 1 is attached to a drawer unit. The drawer unit is housed inside the image forming device and is pulled out from the image forming device. The drawer unit has a photosensitive drum. When the developing cartridge is attached to the drawer unit, the photosensitive drum and the developing roller face each other.

[0003] Furthermore, the developer cartridge described in Patent Document 2 is mounted to a drum cartridge. The drum cartridge has a photosensitive drum. When the developer cartridge is mounted to the drum cartridge, the photosensitive drum and the developing roller face each other. Then, with the developer cartridge mounted to the drum cartridge, the developer cartridge is mounted to an image forming device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-59510 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-54058 Summary of the Invention [Problem to be solved by the invention]

[0005] Conventionally, a developer cartridge having a storage medium is also known. The storage medium is, for example, an IC chip. The storage medium has an electrical contact surface. The electrical contact surface contacts an electrical connector provided in the image forming device or the drawer unit. However, when the developer cartridge is attached to the image forming device or the drawer unit, the electrical contact surface rubs against a protrusion on the image forming device or the drawer unit.

[0006] SUMMARY OF THE INVENTION An object of the present invention is to provide a structure that can suppress rubbing of electrical contact surfaces when a developing cartridge is installed. [Means for solving the problem]

[0007] In order to solve the above problem, the first invention of the present application is a developer cartridge comprising: a housing that contains developer inside; a storage medium having an electrical contact surface; an elastic member that extends in a first direction intersecting the electrical contact surface, the elastic member being expandable and contractible in the first direction between a first state and a second state; and a holder in which the electrical contact surface is located on an outer surface in the first direction, the position of the outer surface relative to the housing being movable in the first direction between a first position and a second position, wherein the length in the first direction of the elastic member in the first state is longer than the length in the first direction of the elastic member in the second state, and when the elastic member is in the first state, the holder is located at the first position, and when the elastic member is in the second state, the holder is located at the second position.

[0008] The second invention of the present application is a developing cartridge of the first invention, wherein the holder includes a first end including the outer surface and a second end spaced apart from the first end in the first direction, and the elastic member is positioned between the first end and the second end in the first direction.

[0009] The third invention of the present application is a developing cartridge of the second invention, wherein the distance in the first direction between the first end and the second end in the first state is longer than the distance in the first direction between the first end and the second end in the second state.

[0010] The fourth invention of the present application is a developing cartridge according to any one of the first to third inventions, wherein the position of the outer surface relative to the housing is movable in the first direction between the first position, the second position, and a third position, the elastic member is expandable and contractible in the first direction between the first state, the second state, and the third state, the length of the elastic member in the first direction in the first state is longer than the length of the elastic member in the second state, the length of the elastic member in the first direction in the third state is longer than the length of the elastic member in the first direction in the second state, and when the elastic member is in the third state, the holder is located at the third position.

[0011] The fifth invention of the present application is a developing cartridge of the second invention, wherein the position of the outer surface relative to the housing is movable in the first direction between the first position, the second position, and a third position, the elastic member is expandable and contractible in the first direction between the first state, the second state, and the third state, the length of the elastic member in the first direction in the first state is longer than the length of the elastic member in the second state, and the distance in the first direction between the first end and the second end in the first state is longer than the distance in the first direction between the first end and the second end in the second state, the length of the elastic member in the first direction in the third state is longer than the length of the elastic member in the first direction in the second state, and the distance in the first direction between the first end and the second end in the third state is longer than the distance in the first direction between the first end and the second end in the second state, and when the elastic member is in the third state, the holder is located at the third position.

[0012] The sixth invention of the present application is a developer cartridge according to any one of the first to fifth inventions, wherein the position of the outer surface relative to the housing is movable from the first position to the second position depending on the installation of the developer cartridge to an image forming device, and in the first position, a portion of the holder and the electrical contact surface are in a non-contact state where they do not contact a portion of the image forming device, and in the second position, a portion of the holder or the electrical contact surface is in a contact state where they contact the portion of the image forming device.

[0013] The seventh invention of the present application is a developing cartridge according to the fourth or fifth invention, wherein the position of the outer surface relative to the housing is movable from the first position via the second position to the third position depending on the installation of the developing cartridge to an image forming device, and in the first position, a portion of the holder and the electrical contact surface are in a non-contact state where they do not contact a portion of the image forming device, in the second position, a portion of the holder or the electrical contact surface is in a contact state where they contact a portion of the image forming device, and in the third position, the electrical contact surface is in a connector contact state where it contacts an electrical connector of the image forming device.

[0014] An eighth aspect of the present invention is the developing cartridge according to the fourth, fifth or seventh aspect, wherein the length of the elastic member in the first direction in the third state is shorter than the natural length of the elastic member.

[0015] A ninth aspect of the present invention is the developing cartridge according to any one of the first to eighth aspects, wherein the first direction is a direction perpendicular to the electrical contact surface.

[0016] A tenth aspect of the present invention is the developing cartridge according to any one of the first to ninth aspects, wherein the holder is movable together with the storage medium.

[0017] An eleventh aspect of the present invention is the developing cartridge according to any one of the first to tenth aspects, wherein the holder holds the electrical contact surface on the outer surface.

[0018] A twelfth aspect of the present invention is the developing cartridge according to any one of the first to eleventh aspects, wherein the storage medium is located on an outer surface of the holder.

[0019] A thirteenth aspect of the present invention is the developing cartridge of the twelfth aspect, wherein the holder holds the storage medium on the outer surface.

[0020] A fourteenth aspect of the present invention is the developing cartridge according to any one of the first to thirteenth aspects of the present invention, further comprising a developing roller rotatable about a shaft extending in a direction different from the first direction.

[0021] A fifteenth aspect of the present invention is the developing cartridge according to any one of the first to fourteenth aspects, wherein the holder is located on a side of the housing.

[0022] The 16th invention of the present application is a developing cartridge according to any one of the 1st to 15th inventions, wherein the outer surface has a first surface located on one side of the electrical contact surface in a second direction different from the first direction, and the first surface is inclined with respect to the electrical contact surface.

[0023] The 17th invention of the present application is a developing cartridge of the 16th invention, further comprising a developing roller rotatable about an axis extending in a third direction different from the first direction, the developing roller being located on one side of the housing in the second direction.

[0024] The 18th invention of the present application is a developer cartridge of the 16th or 17th invention, wherein the first surface extends from a third position toward the electrical contact surface to a fourth position, and in the first direction, the third position is farther from the electrical contact surface than the fourth position.

[0025] The 19th invention of the present application is a developing cartridge of the 18th invention, wherein the distance in the first direction between the third position and the fourth position is greater than the distance in the first direction between the electrical contact surface and the fourth position.

[0026] The 20th invention of the present application is a developer cartridge according to any one of the 16th to 19th inventions, wherein the first surface is a first guide surface that can contact a part of the image forming device when the developer cartridge is attached to the image forming device.

[0027] The 21st invention of the present application is a developing cartridge according to any one of the 16th to 20th inventions, wherein the outer surface has a second surface located on the other side of the electrical contact surface in the second direction, the second surface being inclined with respect to the electrical contact surface.

[0028] The 22nd invention of the present application is a developing cartridge of the 21st invention, further comprising a developing roller rotatable about an axis extending in a third direction different from the first direction, the developing roller being located on one side of the housing in the second direction.

[0029] The 23rd invention of the present application is a developer cartridge of the 21st or 22nd invention, wherein the second surface extends from a fifth position toward the electrical contact surface to a sixth position, and in the first direction, the fifth position is farther from the electrical contact surface than the sixth position.

[0030] The 24th invention of the present application is a developing cartridge of the 23rd invention, wherein the distance in the first direction between the fifth position and the sixth position is greater than the distance in the first direction between the electrical contact surface and the sixth position.

[0031] The 25th invention of the present application is a developer cartridge according to any one of the 21st to 24th inventions, wherein the second surface is a second guide surface that can contact a part of the image forming device when the developer cartridge is attached to the image forming device.

[0032] The 26th invention of the present application is a developing cartridge according to any one of the 1st to 25th inventions, wherein the outer surface has third surfaces located on both sides of the electrical contact surface in a third direction different from the first direction, and in the first direction, the third surfaces are farther from the elastic member than the electrical contact surfaces.

[0033] A 27th invention of the present application is the developer cartridge of the 26th invention, wherein the third surface is a third guide surface that can come into contact with a part of the image forming device when the developer cartridge is attached to the image forming device.

[0034] The 28th invention of the present application is a developing cartridge of the 26th or 27th invention, further comprising a developing roller rotatable about an axis extending in the third direction, the developing roller being located on one side of the housing in the second direction.

[0035] A twenty-ninth aspect of the present invention is the developing cartridge according to any one of the first to twenty-eighth aspects, wherein the elastic member is a spring.

[0036] A 30th aspect of the present invention is the developing cartridge of the 29th aspect, wherein the spring is a coil spring.

[0037] A thirty-first aspect of the present invention is the developing cartridge of the twelfth or thirteenth aspect, wherein the storage medium has the electrical contact surface. [Effects of the Invention]

[0038] According to the first to thirty-first aspects of the present application, it is possible to suppress abrasion of the electrical contact surfaces when the developing cartridge is attached.

[0039] According to the second aspect of the present invention, an elastic member is provided between the first and second ends of the holder, allowing the first end, including the outer surface, to move in the first direction relative to the second end, thereby preventing friction on the electrical contact surfaces when the developer cartridge is installed in the image forming device.

[0040] According to the third aspect of the present invention, the distance in the first direction between the first end and the second end in the first state is longer than the distance in the first direction between the first end and the second end in the second state. Therefore, the distance of the first end, including the outer surface, relative to the second end can be changed. This reduces friction on the electrical contact surfaces when the developer cartridge is installed in an image forming device.

[0041] According to the fourth aspect of the present invention, the position of the outer surface of the holder that holds the electrical contact surface can be further moved in the first direction from the second position to the third position, thereby suppressing friction on the electrical contact surface when the developer cartridge is installed in the image forming apparatus.

[0042] According to the fifth aspect of the present invention, an elastic member is provided between the first and second ends of the holder, which allows the first end, including the outer surface, to move in the first direction relative to the second end, and also allows the position of the outer surface of the holder that holds the electrical contact surface to be changed from a second position to a third position in the first direction, thereby preventing friction on the electrical contact surface when the developer cartridge is installed in the image forming apparatus.

[0043] Furthermore, according to the sixth aspect of the present invention, even if the holder can come into contact with a part of the image forming device, the holder can move from the first position to the second position, thereby suppressing friction of the electrical contact surfaces when the developing cartridge is attached to the image forming device.

[0044] According to the seventh aspect of the present invention, the position of the outer surface of the holder that holds the electrical contact surface can be further moved in the first direction from the second position to the third position, and at the third position, the electrical contact surface can come into contact with the electrical connector of the image forming device. This reduces friction on the electrical contact surface when the developer cartridge is installed in the image forming device, and the electrical contact can come into contact with the electrical connector of the image forming device.

[0045] Furthermore, according to the eighth invention of the present application, the length of the elastic member in the first direction in the third state is shorter than the natural length of the elastic member, so that in the third position the electrical contact surface can receive the repulsive force of the elastic member.

[0046] Furthermore, according to the tenth aspect of the present invention, the storage medium can also be moved together with the holder.

[0047] Furthermore, according to the eleventh aspect of the present invention, the holder can hold the electrical contact surface on the outer surface.

[0048] According to a twelfth aspect of the present invention, the storage medium can be located on the outer surface.

[0049] Furthermore, according to the thirteenth aspect of the present invention, the holder can hold the storage medium on its outer surface.

[0050] Furthermore, according to the 16th invention of the present application, by having a first surface that is inclined relative to the electrical contact surface, the first surface can guide the holder when the developer cartridge is attached to or detached from the image forming device.

[0051] Furthermore, according to the 18th invention of the present application, by having a first surface that is inclined relative to the electrical contact surface, the first surface can guide the holder when the developer cartridge is attached to or detached from the image forming device.

[0052] Furthermore, according to the 19th invention of the present application, by having a first surface that is inclined relative to the electrical contact surface, the first surface can guide the holder when the developer cartridge is attached to or detached from the image forming device.

[0053] Furthermore, according to the 20th invention of the present application, by having a first guide surface that is inclined relative to the electrical contact surface, the first guide surface can guide the holder when the developer cartridge is attached to or detached from the image forming device.

[0054] Furthermore, according to the 21st invention of the present application, by having a second surface inclined relative to the electrical contact surface, the second surface can guide the holder when the developer cartridge is attached to or detached from the image forming device.

[0055] Furthermore, according to the 23rd invention of the present application, by having a second surface inclined relative to the electrical contact surface, the second surface can guide the holder when the developer cartridge is attached to or detached from the image forming device.

[0056] Furthermore, according to the 24th invention of the present application, by having a second surface inclined relative to the electrical contact surface, the second surface can guide the holder when the developer cartridge is attached to or detached from the image forming device.

[0057] Furthermore, according to the 25th invention of the present application, by having a second guide surface inclined relative to the electrical contact surface, the holder can be guided by the second guide surface when the developing cartridge is attached to or detached from the image forming device.

[0058] Furthermore, according to the 26th invention of the present application, by having a third surface that is inclined relative to the electrical contact surface, when the developing cartridge is attached to or detached from the image forming device, the third surface can suppress rubbing of the electrical contact surface when the developing cartridge is attached to or detached from the image forming device.

[0059] Furthermore, according to the 27th invention of the present application, by having a third guide surface that is inclined relative to the electrical contact surface, when the developing cartridge is attached to or detached from the image forming device, the third guide surface can suppress friction of the electrical contact surface when the developing cartridge is attached to or detached from the image forming device.

[0060] According to the twenty-eighth aspect of the present invention, when the developer cartridge is attached to the image forming apparatus, the protrusions of the image forming apparatus do not come into contact with the electrical contact surfaces, thereby further preventing damage to the electrical contact surfaces. [Brief explanation of the drawings]

[0061] [Figure 1] FIG. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. [Figure 6] FIG. 2 is an exploded perspective view of an IC chip assembly. [Figure 7] FIG. 2 is a cross-sectional view of an IC chip assembly. [Figure 8] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 9] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 10] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 11] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 12] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 13] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 14] FIG. 10 is a diagram illustrating a state in which a developing cartridge is being mounted. [Figure 15] FIG. 10 is a diagram showing a state when a separating operation is performed. [Figure 16] FIG. 10 is a partially exploded perspective view of a developing cartridge according to a first modified example. [Figure 17] FIG. 10 is a cross-sectional view of an IC chip assembly according to a first modified example. [Figure 18] FIG. 10 is a partial perspective view of a developing cartridge according to a second modified example. [Figure 19] 10A and 10B are diagrams showing the movement of the columnar elastic body and the IC chip assembly of the second modified example. [Figure 20] 10A and 10B are diagrams showing the movement of the columnar elastic body and the IC chip assembly of the second modified example. [Figure 21] FIG. 10 is a diagram illustrating a state in which a developing cartridge according to a second modified example is attached. [Figure 22] FIG. 10 is a diagram illustrating a state in which a developing cartridge according to a second modified example is attached. [Figure 23] 10A and 10B are diagrams illustrating a state when a separating operation of the developing cartridge of the second modified example is performed. [Figure 24] FIG. 11 is a perspective view of a developing cartridge according to a third modified example. [Figure 25] FIG. 10 is a view of a developing cartridge according to a third modified example, as viewed from one side in the third direction. [Figure 26] FIG. 10 is a view of a developing cartridge according to a third modified example, as viewed from one side in the third direction. [Figure 27] FIG. 10 is a view of a developing cartridge according to a third modified example, as viewed from one side in the third direction. [Figure 28] FIG. 11 is an exploded perspective view of a first cover and an IC chip assembly according to a fourth modified example. [Figure 29] FIG. 10 is a cross-sectional view of a first cover and an IC chip assembly according to a fourth modified example. [Figure 30] FIG. 10 is a perspective view of an IC chip assembly according to a fourth modified example. [Figure 31] FIG. 13 is a partial perspective view of a developing cartridge according to a fifth modified example. [Figure 32] FIG. 13 is an exploded perspective view of a first cover and an IC chip assembly according to a fifth modified example. [Figure 33] FIG. 13 is a perspective view of a developing cartridge and a drum cartridge according to a sixth modified example. [Figure 34] FIG. 13 is a diagram illustrating a state in which a drum cartridge according to a sixth modified example is mounted in an image forming apparatus. [Figure 35] FIG. 13 is an exploded perspective view of the vicinity of an IC chip assembly according to a sixth modified example. DETAILED DESCRIPTION OF THE INVENTION

[0062] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0063] In the following, the direction intersecting the electrical contact surface (in this embodiment, the direction "perpendicular" to the electrical contact surface) is referred to as the "first direction." The direction in which the casing 10 moves during the separation operation described below is referred to as the "second direction." The direction in which the rotation axis of the developing roller extends is referred to as the "third direction."

[0064] <1. Overall structure of the developing cartridge> 1 to 5 are perspective views of a developer cartridge 1 according to one example of the present invention. The developer cartridge 1 is used in an electrophotographic image forming apparatus (e.g., a laser printer or an LED printer) and is a unit that supplies a developer (e.g., toner) to a photosensitive drum. As shown in FIG. 1, the developer cartridge 1 of this embodiment is attached to a drawer unit 90 provided in the image forming apparatus. When replacing the developer cartridge 1, the drawer unit 90 is pulled out from the front of the image forming apparatus. Then, the developer cartridges 1 are attached to four cartridge holders 91 provided in the drawer unit 90. Each of the four cartridge holders 91 is provided with a photosensitive drum.

[0065] In this embodiment, four developer cartridges 1 are attached to one drawer unit 90. The four developer cartridges 1 contain developers of different colors (for example, cyan, magenta, yellow, and black). However, the number of developer cartridges 1 attached to the drawer unit 90 may be one to three, or may be five or more.

[0066] As shown in FIGS. 2 to 5, the developing cartridge 1 of this embodiment includes a casing 10, an agitator 20, a developing roller 30, a first gear portion 40, a second gear portion 50, and an IC chip assembly 60.

[0067] The developing roller 30 is a roller that can rotate around a rotation axis that extends in the third direction. The developing roller 30 of this embodiment has a roller main body 31 and a roller shaft 32. The roller main body 31 is a cylindrical member that extends in the third direction. The roller main body 31 is made of a material such as elastic rubber. The roller shaft 32 is a cylindrical member that penetrates the roller main body 31 in the third direction. The roller shaft 32 is made of a material such as metal or conductive resin.

[0068] The roller shaft 32 does not have to penetrate the roller body 31 in the third direction. For example, a pair of roller shafts 32 may extend in the third direction from both ends of the roller body 31 in the third direction.

[0069] The agitator 20 has an agitator shaft 21 and an agitator blade 22. The agitator shaft 21 extends along a rotation axis extending in the third direction. The agitator blade 22 extends radially outward from the agitator shaft 21. The agitator blade 22 is disposed within the developer chamber 13 of the casing 10. A first agitator gear 44 and a second agitator gear 51, which will be described later, are respectively connected to both ends of the agitator shaft 21 in the third direction. Therefore, the agitator shaft 21 and the agitator blade 22 rotate together with the first agitator gear 44 and the second agitator gear 51. When the agitator blade 22 rotates, the developer in the developer chamber 13 is agitated.

[0070] The casing 10 is a housing capable of containing a developer (e.g., toner) for electrophotographic printing. The casing 10 has a first outer surface 11 and a second outer surface 12. The first outer surface 11 and the second outer surface 12 are spaced apart from each other in a third direction. The first gear portion 40 and the IC chip assembly 60 are located on the first outer surface 11. The second gear portion 50 is located on the second outer surface 12. The casing 10 extends in the third direction between the first outer surface 11 and the second outer surface 12. A developer chamber 13 that contains a developer is provided inside the casing 10.

[0071] The casing 10 has an opening 14. The opening 14 connects the developer chamber 13 to the outside. The opening 14 is located at one end of the casing 10 in the second direction. The developing roller 30 is located at the opening 14. That is, the developing roller 30 is located on one side of the center of the casing 10 in the second direction. The roller body 31 is fixed to the roller shaft 32 so as not to rotate relative to it. Furthermore, one end of the roller shaft 32 in the third direction is fixed to the developing gear 42, which will be described later, so as not to rotate relative to it. Therefore, when the developing gear 42 rotates, the roller shaft 32 also rotates, and the roller body 31 rotates together with the roller shaft 32.

[0072] When the developer cartridge 1 receives a driving force, developer is supplied from the developer chamber 13 in the casing 10 to the outer circumferential surface of the developing roller 30 via a supply roller (not shown). At this time, the developer is frictionally charged between the supply roller and the developing roller 30. Meanwhile, a bias voltage is applied to the roller shaft 32 of the developing roller 30. Therefore, the developer is attracted to the outer circumferential surface of the roller body 31 by the electrostatic force between the roller shaft 32 and the developer.

[0073] The developer cartridge 1 also has a layer thickness regulating blade (not shown). The layer thickness regulating blade regulates the developer supplied to the outer peripheral surface of the roller body 31 to a uniform thickness. The developer on the outer peripheral surface of the roller body 31 is then supplied to a photosensitive drum provided in the drawer unit 90. At this time, the developer moves from the roller body 31 to the photosensitive drum in accordance with the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum. This makes the electrostatic latent image visible on the outer peripheral surface of the photosensitive drum.

[0074] The first gear portion 40 is located on one side of the casing 10 in the third direction. That is, the first gear portion 40 is located on the first outer surface 11. FIG. 4 is a perspective view of the developer cartridge 1 with the first gear portion 40 disassembled. As shown in FIG. 4, the first gear portion 40 has a coupling 41, a development gear 42, an idle gear 43, a first agitator gear 44, and a first cover 45. Note that the multiple gear teeth of each gear are not shown in FIG. 4.

[0075] The coupling 41 is a gear that initially receives the driving force supplied from the image forming apparatus. The coupling 41 is capable of rotating around a rotation axis extending in the third direction. The coupling 41 has a coupling portion 411 and a coupling gear 412. The coupling portion 411 and the coupling gear 412 are formed, for example, from a single piece of resin. The coupling portion 411 is provided with a fastening hole 413 that is recessed in the third direction. Furthermore, the outer periphery of the coupling gear 412 is provided with a plurality of gear teeth at equal intervals around the entire circumference.

[0076] When the drawer unit 90 with the developer cartridge 1 attached is stored in the image forming apparatus, the drive shaft of the image forming apparatus is inserted into the fastening hole 413 of the coupling part 411. This connects the drive shaft and the coupling part 411 so that they cannot rotate relative to each other. Therefore, when the drive shaft rotates, the coupling part 411 rotates, and the coupling gear 412 rotates together with the coupling part 411.

[0077] The developing gear 42 is a gear for rotating the developing roller 30. The developing gear 42 is rotatable around a rotation axis extending in the third direction. A plurality of gear teeth are provided at equal intervals around the outer periphery of the developing gear 42. At least some of the gear teeth of the coupling gear 412 and at least some of the gear teeth of the developing gear 42 mesh with each other. The developing gear 42 is fixed to the end of the roller shaft 32 of the developing roller 30 in the third direction so as not to rotate relative to the developing gear 42. Therefore, when the coupling gear 412 rotates, the developing gear 42 rotates, and the developing roller 30 rotates together with the developing gear 42.

[0078] The idle gear 43 is a gear for transmitting the rotation of the coupling gear 412 to the first agitator gear 44. The idle gear 43 is rotatable around a rotation axis extending in the third direction. The idle gear 43 has a large diameter gear portion 431 and a small diameter gear portion 432 arranged in the third direction. The small diameter gear portion 432 is located between the large diameter gear portion 431 and the first outer surface 11 of the casing 10. In other words, the large diameter gear portion 431 is farther from the first outer surface 11 than the small diameter gear portion 432. The diameter of the small diameter gear portion 432 is smaller than the diameter of the large diameter gear portion 431. In other words, the diameter of the tip circle of the small diameter gear portion 432 is smaller than the diameter of the tip circle of the large diameter gear portion 431. The large diameter gear portion 431 and the small diameter gear portion 432 are formed, for example, from a single piece of resin.

[0079] The large diameter gear portion 431 and the small diameter gear portion 432 each have a plurality of gear teeth provided at equal intervals around the entire outer periphery. The number of gear teeth on the small diameter gear portion 432 is smaller than the number of gear teeth on the large diameter gear portion 431. At least some of the gear teeth on the coupling gear 412 and at least some of the gear teeth on the large diameter gear portion 431 mesh with each other. At least some of the gear teeth on the small diameter gear portion 432 and at least some of the gear teeth on the first agitator gear 44 mesh with each other. When the coupling gear 412 rotates, the large diameter gear portion 431 rotates, and the small diameter gear portion 432 rotates together with the large diameter gear portion 431. Then, as the small diameter gear portion 432 rotates, the first agitator gear 44 also rotates.

[0080] The first agitator gear 44 is a gear for rotating the agitator 20 in the developer chamber 13. The first agitator gear 44 is rotatable around a rotation axis extending in the third direction. A plurality of gear teeth are provided at equal intervals around the outer periphery of the first agitator gear 44. As described above, at least some of the gear teeth of the small diameter gear portion 432 and at least some of the gear teeth of the first agitator gear 44 mesh with each other. The first agitator gear 44 is fixed to one end of the agitator shaft 21 in the third direction so as not to rotate relative to the agitator gear 44. Therefore, when power is transmitted from the coupling 41 to the first agitator gear 44 via the idle gear 43, the first agitator gear 44 rotates, and the agitator 20 rotates together with the first agitator gear 44.

[0081] The first cover 45 is fixed to the first outer surface 11 of the casing 10, for example, by screws. The coupling gear 412, the development gear 42, the idle gear 43, and the first agitator gear 44 are housed between the first outer surface 11 and the first cover 45. The fastening holes 413 of the coupling portion 411 are exposed to the outside of the first cover 45. The first cover 45 of this embodiment also serves as a holder cover that holds a holder 62 of the IC chip assembly 60, which will be described later. The structure of the first cover 45 as a holder cover will be described later.

[0082] The second gear portion 50 is located on the other side of the casing 10 in the third direction. That is, the second gear portion 50 is located on the second outer surface 12. FIG. 5 is a perspective view of the developer cartridge 1 with the second gear portion 50 disassembled. As shown in FIG. 5, the second gear portion 50 has a second agitator gear 51, a detection gear 52, a conductive member 53, and a second cover 54. Note that in FIG. 5, the gear teeth of the second agitator gear 51 and the detection gear 52 are not shown.

[0083] The second agitator gear 51 is a gear for transmitting the rotation of the agitator shaft 21 to the detection gear 52. The second agitator gear 51 is rotatable around a rotation axis extending in the third direction. A plurality of gear teeth are provided at equal intervals around the outer periphery of the second agitator gear 51. At least some of the gear teeth of the second agitator gear 51 and at least some of the gear teeth of the detection gear 52 mesh with each other. The second agitator gear 51 is fixed to the other end of the agitator shaft 21 in the third direction so as not to rotate relative to each other. Therefore, when the agitator shaft 21 rotates, the second agitator gear 51 also rotates.

[0084] The detection gear 52 is a gear for transmitting information about the developer cartridge 1 to the image forming apparatus. The information about the developer cartridge 1 includes, for example, information about whether the developer cartridge 1 is a new (unused) developer cartridge or a used developer cartridge. The information about the developer cartridge 1 also includes, for example, specifications of the developer cartridge 1. The specifications of the developer cartridge 1 include, for example, the number of pages that can be printed using the developer contained in the developer cartridge 1 (yield).

[0085] The detection gear 52 is rotatable around a rotation axis extending in the third direction. The detection gear 52 has a plurality of gear teeth on a portion of its outer periphery. When an unused developer cartridge 1 is attached to the drawer unit 90 and the drawer unit 90 is stored in the image forming apparatus, the detection gear 52 rotates by meshing with the second agitator gear 51. When the meshing between the second agitator gear 51 and the detection gear 52 is released, the detection gear 52 stops rotating.

[0086] On the other hand, when a used developer cartridge 1 is attached to the drawer unit 90 and the drawer unit 90 is stored in the image forming apparatus, the detection gear 52 does not rotate because the engagement between the detection gear 52 and the second agitator gear 51 is disengaged.

[0087] Note that another gear may be disposed between the second agitator gear 51 and the detection gear 52. For example, the second gear unit 50 may have a second idle gear that meshes with both the second agitator gear 51 and the detection gear 52. Then, the rotation of the second agitator gear 51 may be transmitted to the detection gear 52 via the second idle gear.

[0088] 5, the detection gear 52 has a detection protrusion 521. The detection protrusion 521 protrudes in the third direction and extends in an arc shape with the rotation axis as the center.

[0089] The conductive member 53 is an electrically conductive member. The conductive member 53 is made of a conductive metal or a conductive resin. The conductive member 53 is located on the second outer surface 12 of the casing 10. The conductive member 53 has a gear shaft 531 protruding in the third direction. The detection gear 52 is supported by the gear shaft 531 and rotates around the gear shaft 531. The conductive member 53 also has a bearing portion 532. The bearing portion 532 contacts the roller shaft 32 of the developing roller 30.

[0090] The drawer unit 90 has a conductive lever (not shown) that contacts the gear shaft 531. When the lever contacts the gear shaft 531, the conductive member 53 and the roller shaft 32 are electrically connected to the lever. When the image forming apparatus is operating, the roller shaft 32 is maintained at a predetermined bias voltage by the power supplied from the lever. However, the detection protrusion 521 partially covers the outer surface of the gear shaft 531. Therefore, when a new developer cartridge 1 is inserted into the drawer unit 90 and the detection gear 52 is rotating, the contact state between the lever and the gear shaft 531 changes depending on the shape of the detection gear 52. By recognizing this change in contact state, the image forming apparatus can determine whether the installed developer cartridge 1 is new and identify the specifications of the developer cartridge 1.

[0091] However, the method for detecting information from the detection gear 52 does not necessarily have to utilize the presence or absence of electrical continuity. For example, the movement of the lever may be optically detected. The circumferential position and length of the detection protrusion 521 may differ from those in this embodiment. The detection gear 52 may also have multiple detection protrusions 521. The shape of the detection gear 52 can be varied depending on the specifications of the developer cartridge 1, such as the number of printable pages. Specifically, the number of detection protrusions 521, the circumferential spacing between the multiple detection protrusions 521, the circumferential length of each detection protrusion 521, and the radial length of each detection protrusion 521 can be varied depending on the specifications. In this way, by providing variations in the number and circumferential position of the detection protrusions 521, various specifications of the developer cartridge 1 can be indicated to the image forming apparatus.

[0092] The detection gear may also be composed of multiple members. For example, the detection gear 52 and the detection protrusion 521 may be separate members. The detection gear may also have a detection gear main body and an auxiliary member whose position changes in response to the rotation of the detection gear main body. The auxiliary member may then change the position of the lever.

[0093] Furthermore, the detection gear 52 may be a movable gear that is movable in the third direction. The movable gear does not have to be a gear with missing teeth. That is, the movable gear may have a plurality of gear teeth circumferentially arranged on its outer circumferential surface. In this case, when the movable gear rotates, the movable gear moves in the third direction, thereby disengaging the movable gear from the second agitator gear 51. The movable gear may move in a direction away from the second outer surface 12 in the third direction. The movable gear may also move in a direction toward the third direction from the second outer surface 12.

[0094] Alternatively, the detection gear 52 may have a cam that comes into contact with the detection protrusion 521. In this case, the cam rotates as the detection gear 52 rotates, and the rotation of the cam brings it into contact with the detection protrusion 521, causing the detection protrusion 521 to move. The detection protrusion 521 may be rotatably attached to a shaft provided on the second outer surface 12 or the second gear cover 54. Alternatively, the shaft of the detection protrusion 521 may be inserted into a hole in the second outer surface 12 or the second gear cover 54, and the detection protrusion 521 may be rotatably held.

[0095] Furthermore, in this embodiment, the gear shaft 531 extends in the third direction from the second outer surface 12. However, the gear shaft 531 does not have to be in direct contact with the second outer surface 12. For example, the casing 10 may further have a through-hole penetrating the second outer surface 12 and a cap attached to the through-hole, and the gear shaft may extend from the cap in the third direction. In this case, for example, the cap has a gear shaft that protrudes in the third direction toward the detection gear 53. The detection gear 53 is supported by the gear shaft and rotates around the gear shaft 531.

[0096] The second cover 54 is fixed to the second outer surface 12 of the casing 10, for example, by screws. The second agitator gear 51, the detection gear 52, and the conductive member 53 are housed between the second outer surface 12 and the second cover 54. The second cover 54 also has an opening 541. A portion of the detection gear 52 and a portion of the gear shaft 531 are exposed through the opening 541. The lever described above comes into contact with the detection gear 52 or the gear shaft 531 through the opening 541.

[0097] <2. IC Chip Assembly> The IC chip assembly 60 is disposed on the first outer surface 11 of the casing 10. FIG. 6 is an exploded perspective view of the IC chip assembly 60. FIG. 7 is a cross-sectional view of the IC chip assembly 60 cut along a plane perpendicular to the third direction. As shown in FIGS. 2 to 7, the IC chip assembly 60 has an IC chip 61, which is a storage medium, and a holder 62 that holds the IC chip 61. The holder 62 is held by the first cover 45 on the side of the casing 10 in the third direction. Various information related to the developer cartridge 1 is recorded on the IC chip 61. The IC chip 61 has an electrical contact surface 611. The electrical contact surface 611 is made of metal, which is a conductor. The IC chip 61 is fixed to the outer surface of the holder 62 in the first direction.

[0098] The drawer unit 90 has an electrical connector. The electrical connector is made of, for example, metal. When the developer cartridge 1 is attached to the drawer unit 90, the electrical connector of the drawer unit 90 comes into contact with the electrical contact surface 611. This allows the image forming apparatus to at least one of read information from and write information to the IC chip 61.

[0099] At least a portion of the holder 62 is covered by the first cover 45. The holder 62 has bosses 621a, 621b, and 621c. The bosses 621a and 621b each extend in the third direction from the surface of the holder 62 opposite the surface facing the casing 10 toward the first cover 45. The bosses 621a and 621b are aligned in the second direction. On the other hand, as shown in FIGS. 2 and 4, the first cover 45 has through holes 451a and 451b. The through holes 451a and 451b each penetrate the first cover 45 in the third direction. The through holes 451a and 451b are aligned in the second direction. The boss 621a is inserted into the through hole 451a. The boss 621b is inserted into the through hole 451b.

[0100] Boss 621c extends in the third direction from the surface of holder 62 facing casing 10 toward casing 10. Meanwhile, casing 10 has recess 15. Recess 15 is recessed in the third direction in first outer surface 11 of casing 10. Boss 621c is inserted into recess 15. Note that each of bosses 621a, 621b, and 621c may have a cylindrical shape or a rectangular pillar shape.

[0101] The size (inner dimension) of through-hole 451a in the second direction is larger than the size (outer dimension) of boss 621a. The size (inner dimension) of through-hole 451b in the second direction is larger than the size (outer dimension) of boss 621b in the second direction. Furthermore, the size (inner dimension) of recess 15 in the second direction is larger than the size (outer dimension) of boss 621c in the second direction. Therefore, holder 62, together with bosses 621a, 621b, and 621c, can move in the second direction relative to casing 10 and first cover 45. When holder 62 moves in the second direction, IC chip 61 having electrical contact surface 611 also moves in the second direction together with holder 62.

[0102] Furthermore, the size (inner dimension) of through-hole 451a in the first direction is larger than the size (outer dimension) of boss 621a in the first direction. The size (inner dimension) of through-hole 451b in the first direction is larger than the size (outer dimension) of boss 621b in the first direction. Furthermore, the size (inner dimension) of recess 15 in the first direction is larger than the size (outer dimension) of boss 621c in the first direction. Therefore, holder 62, together with bosses 621a, 621b, and 621c, can move in the first direction relative to casing 10 and first cover 45. When holder 62 moves in the first direction, IC chip 61 having electrical contact surface 611 also moves in the first direction together with holder 62. Furthermore, holder 62 may be movable in a third direction between first cover 45 and first outer surface 11.

[0103] The number of bosses provided on holder 62 may be one or three or more. The number of through holes provided on first cover 45 may also be one or three or more. First cover 45 may have recesses into which bosses 621a and 621b are inserted, instead of through holes 451a and 451b.

[0104] As shown in FIGS. 6 and 7 , the holder 62 has a first end 710 and a second end 720. The first end 710 is one end of the holder 62 in the first direction. The second end 720 is the other end of the holder 62 in the first direction. The first end 710 is movable in the first direction relative to the second end 720. More specifically, the holder 62 of this embodiment has a first holder member 71, a second holder member 72, and a coil spring 73 located therebetween. The first holder member 71 is made of, for example, resin. The second holder member 72 is made of, for example, resin. The first holder member 71 has the first end 710. The IC chip 61 is fixed to a holding surface 620 included in the outer surface of the first end 710. The second holder member 72 has the second end 720. In the assembled holder 62, the first end 710 and the second end 720 are spaced apart in the first direction.

[0105] The coil spring 73 is an elastic member that extends in a first direction. The coil spring 73 is disposed between a first end 710 and a second end 720 in the first direction. The coil spring 73 expands and contracts in the first direction at least between a first state and a second state that is more contracted than the first state. The length of the coil spring 73 in the first direction in the first state is longer than the length of the coil spring 73 in the first direction in the second state. Therefore, the distance in the first direction between the first end 710 and the second end 720 in the first state is longer than the distance in the first direction between the first end 710 and the second end 720 in the second state. Furthermore, the length of the coil spring 73 in the first direction in at least the second state is shorter than the natural length of the coil spring 73.

[0106] 6 and 7, the first holder member 71 has claw portions 714a and 714b. The claw portions 714a and 714b each protrude from the first holder member 71 in a direction intersecting the first direction. Meanwhile, the second holder member 72 has openings 721a and 721b. The claw portion 714a is inserted into the opening 721a. The claw portion 714b is inserted into the opening 721b. In the first state, the claw portion 714a contacts the second holder member 72 at the edge of the opening 721a on the first end 710 side. In the first state, the claw portion 714b contacts the second holder member 72 at the edge of the opening 721b on the first end 710 side. This prevents the length of the coil spring 73 in the first direction from becoming longer than in the first state. Furthermore, the first holder member 71 is prevented from being removed from the second holder member 72. On the other hand, in the second state, the claws 714a and 714b are separated from the second holder member 72.

[0107] Instead of the opening, a recess or a step that can come into contact with the claw may be provided. Also, the opening, recess or step may be provided in the first holder member 71, and the claw may be provided in the second holder member 72.

[0108] The holding surface 620 of the holder 62 can move in a first direction relative to the casing 10 due to the dimensional difference between the through-hole 451 and the boss 621 and the expansion and contraction of the coil spring 73. Hereinafter, the position of the holding surface 620 in the first direction relative to the casing 10 before the developer cartridge 1 is attached to the drawer unit 90 will be referred to as the “initial position” (first position). Furthermore, the position of the holding surface 620 in the first direction relative to the casing 10 at the moment when the coil spring 73 is most contracted during attachment of the developer cartridge 1 to the drawer unit 90 will be referred to as the “intermediate position” (second position). Furthermore, the position of the holding surface 620 in the first direction relative to the casing 10 when the electrical contact surface 611 contacts an electrical connector 913 (described later) will be referred to as the “contact position” (third position). Furthermore, the position of the holding surface 620 in the first direction relative to the casing 10 after attachment of the developer cartridge 1 to the drawer unit 90 is completed will be referred to as the “final position” (fourth position).

[0109] In addition to the holding surface 620 described above, the outer surface of the first end 710 further has a first guide surface 711 (first surface), a second guide surface 712 (second surface), and third guide surfaces 713a, 713b (third surface).

[0110] The first guide surface 711 is provided on one of both side portions of the holding surface 620 in the second direction that is closer to the developing roller 30. The first guide surface 711 is inclined with respect to the electrical contact surface 611 of the IC chip 61 held on the holding surface 620. In detail, the first guide surface 711 is inclined at an acute angle with respect to the electrical contact surface 611.

[0111] Here, one end of the first end portion 710 in the second direction is defined as a first outer end position (third position) 711a. Furthermore, one end of the holding surface 620 in the second direction is defined as a first inner end position (fourth position) 711b. As shown in FIG. 7, the first guide surface 711 extends from the first outer end position 711a toward the electrical contact surface 611 to the first inner end position 711b. In both the second direction and the first direction, the first outer end position 711a is farther from the electrical contact surface 611 than the first inner end position 711b. Furthermore, as shown in FIG. 7, a distance d1 in the first direction between the first outer end position 711a and the first inner end position 711b is greater than a distance d2 in the first direction between the electrical contact surface 611 and the first inner end position 711b.

[0112] The second guide surface 712 is provided on one of both side portions of the holding surface 620 in the second direction, the side farther from the developing roller 30. The second guide surface 712 is inclined with respect to the electrical contact surface 611 of the IC chip 61 held on the holding surface 620. In detail, the second guide surface 712 is inclined at an acute angle with respect to the electrical contact surface 611.

[0113] Here, the other end of the first end 710 in the second direction is defined as a second outer end position (fifth position) 712a. The other end of the holding surface 620 in the second direction is defined as a second inner end position (sixth position) 712b. As shown in FIG. 7 , the second guide surface 712 extends from the second outer end position 712a toward the electrical contact surface 611 to the second inner end position 712b. In both the second direction and the first direction, the second outer end position 712a is farther from the electrical contact surface 611 than the second inner end position 712b. Also, as shown in FIG. 7 , a distance d3 in the first direction between the second outer end position 712a and the second inner end position 712b is greater than a distance d4 in the first direction between the electrical contact surface 611 and the second inner end position 712b.

[0114] The third guide surface 713a is provided on one of both sides of the electrical contact surface 611 in the third direction. The third guide surface 713b is provided on the other of both sides of the electrical contact surface 611 in the third direction. The third guide surfaces 713a and 713b each extend in the second direction. Furthermore, in the first direction, the third guide surfaces 713a and 713b are farther from the coil spring 73 than the electrical contact surface 611. Therefore, the electrical contact surface 611 is disposed at a position recessed toward the coil spring 73 than the third guide surfaces 713a and 713b.

[0115] The first guide surface 711, the second guide surface 712, and the third guide surfaces 713a and 713b may each be flat or curved. However, it is preferable that the first guide surface 711, the second guide surface 712, and the third guide surfaces 713a and 713b are each smooth and without steps so that the developer cartridge 1 does not get caught when it is attached to the drawer unit 90.

[0116] <3. Operation when worn> Next, a description will be given of the operation when the developer cartridge 1 is attached to the drawer unit 90. Figures 8 to 14 are diagrams showing how the developer cartridge 1 is attached to one cartridge holding portion 91 of the drawer unit 90.

[0117] When the developer cartridge 1 is mounted in the cartridge holding portion 91, first, as shown in FIG. 8, the developing roller 30 of the developer cartridge 1 faces the insertion opening 910 of the cartridge holding portion 91. At this time, the first end 710 and the second end 720 of the holder 62 are not yet in contact with the drawer unit 90. Therefore, the coil spring 73 is in the first state described above. Also, the position of the holding surface 620 in the first direction relative to the casing 10 is in the initial position described above. The developer cartridge 1 is inserted in the second direction relative to the cartridge holding portion 91, as indicated by the dashed arrow in FIG. 8.

[0118] The cartridge holding section 91 has a first guide plate 911 and a second guide plate 912. The first guide plate 911 and the second guide plate 912 are arranged facing each other with a gap in the first direction. The first guide plate 911 and the second guide plate 912 extend along the third direction and the second direction, respectively. The first guide plate 911 also has a metallic electrical connector 913 that can come into contact with the electrical contact surface 611 of the IC chip 61. The electrical connector 913 protrudes in the first direction from the surface of the first guide plate 911 toward the second guide plate 912.

[0119] When the developer cartridge 1 is inserted into the cartridge holding portion 91, as shown in FIG. 9, the first guide surface 711 of the holder 62 comes into contact with the end of the first guide plate 911 in the second direction. Then, the first guide surface 711 is pressed by the first guide plate 911, causing the holder 62 to move in the first direction. The movement of the holder 62 at this time is a relative movement with respect to the casing 10. As a result, the holder 62 is positioned in the first direction between the first guide plate 911 and the second guide plate 912, as shown in FIG.

[0120] Thereafter, the first end 710 of the first holder member 71 comes into contact with the first guide plate 911. Additionally, the second end 720 of the second holder member 72 comes into contact with the second guide plate 912. The coil spring 73 contracts in the first direction more than in the first state.

[0121] As shown in FIG. 11 , the first guide plate 911 has a guide protrusion 914 that protrudes toward the second guide plate 912. The guide protrusion 914 is located closer to the insertion opening 910 than the electrical connector 913. The guide protrusion 914 has a first inclined surface 915. The second guide plate 912 has a second inclined surface 916. The distance in the first direction between the first inclined surface 915 and the second inclined surface 916 gradually decreases toward the insertion direction of the developer cartridge 1.

[0122] When the developer cartridge 1 is further inserted in the second direction, the first holder member 71 contacts the first inclined surface 915, and the second holder member 72 contacts the second inclined surface 916. As a result, the first holder member 71 and the second holder member 72 approach each other in the first direction, and the length of the coil spring 73 in the first direction gradually shortens. Eventually, when the third guide surfaces 713a and 713b of the first holder member 71 contact the top of the guide protrusion 914, the length of the coil spring 73 in the first direction becomes the shortest. In other words, the coil spring 73 enters the second state described above. Furthermore, the position of the holding surface 620 in the first direction relative to the casing 10 becomes the intermediate position described above.

[0123] In this way, the IC chip assembly 60 can change the position of the holding surface 620 that holds the IC chip 61 in the first direction when the developer cartridge 1 is inserted into the drawer unit 90. Therefore, the developer cartridge 1 can be inserted while changing the position of the holding surface 620 in the first direction along the guide protrusion 914. Furthermore, compared to when the developer cartridge 1 passes through the guide protrusion 914 with the position of the holding surface 620 in the first direction fixed, the pressure in the first direction applied from the guide protrusion 914 to the first holder member 71 is reduced. Therefore, the developer cartridge 1 can be inserted into the drawer unit 90 while suppressing friction on the electrical contact surface 611 of the IC chip 61. Furthermore, as shown in FIGS. 10 , 11 , and 12 , after the first surface 711 moves over the guide protrusion 914, the electrical contact surface 611 directly contacts the electrical connector 913. This also reduces friction on the electrical connector 913.

[0124] In particular, in the developing cartridge 1 of this embodiment, the electrical contact surface 611 of the IC chip 61 is disposed at a position recessed from the third guide surfaces 713a and 713b. Therefore, in the state shown in Figure 11, the top of the guide protrusion 914 contacts only the third guide surfaces 713a and 713b, and does not contact the electrical contact surface 611. Therefore, it is possible to prevent the guide protrusion 914 from rubbing against the electrical contact surface 611.

[0125] Thereafter, when the developer cartridge 1 is further inserted in the second direction, the third guide surfaces 713a and 713b pass by the guide protrusion 914. Then, as shown in FIG. 12, the second guide surface 712 comes into contact with the guide protrusion 914. Accordingly, the coil spring 73 expands again from the second state to the third state described above. As a result, as shown in FIG. 13, the electrical contact surface 611 of the IC chip 61 comes into contact with the electrical connector 913. The length of the coil spring 73 in the first direction in the third state is shorter than the length of the coil spring 73 in the first state and longer than the length of the coil spring 73 in the first direction in the second state. Furthermore, the length of the coil spring 73 in the first direction in the third state is shorter than the natural length of the coil spring 73. Furthermore, the relative position of the holding surface 620 with respect to the casing 10 in the first direction is the contact position described above.

[0126] As a result, the IC chip assembly 60 is fixed in a sandwiched state between the electrical connector 913 and the second guide plate 912. Then, in this embodiment, the casing 10 is tilted in the first direction as indicated by the dashed arrow in FIG. 14 . As a result, the developing roller 30 contacts the photosensitive drum 92 of the drawer unit 90. At this time, the position of the holding surface 620 relative to the casing 10 in the first direction changes from the contact position to the final position. Furthermore, the boss 621 moves in the first direction within the through-hole 451. As a result, the boss 621 is no longer in contact with the edge of the through-hole 451 of the first cover 45. As a result, the IC chip assembly 60 and the first cover 45 are no longer in contact with each other. Therefore, vibrations are less likely to be transmitted from the driving unit, such as the first gear unit 40, to the IC chip assembly 60 during printing operations in the image forming apparatus. This allows for better maintenance of contact between the electrical contact surface 611 and the electrical connector 913.

[0127] <4. Separation operation> After the developer cartridge 1 is installed, the drawer unit 90 can perform a so-called "separating operation" to temporarily separate the developer roller 30 from the photosensitive drum 92. As shown in FIG. 2, the first cover 45 of the developer cartridge 1 has a first columnar protrusion 46 extending in the third direction. Also, as shown in FIG. 3, the second cover 54 of the developer cartridge 1 has a second columnar protrusion 55 extending in the third direction. Meanwhile, as shown in FIG. 1, the drawer unit 9 has a plurality of pressing members 93. The pressing members 93 are provided on both sides of each cartridge holding portion 91 in the third direction.

[0128] 14, the first columnar projection 46 and the second columnar projection 55 are each pressed by the pressing member 93. This causes the casing 10 to tilt in the first direction. As a result, the position of the holding surface 620 in the first direction relative to the casing 10 changes from the contact position described above to the final position.

[0129] FIG. 15 is a diagram showing a state when the separating operation is performed. During the separating operation, the positions of the first columnar projection 46 and the second columnar projection 55 change due to a driving force from the image forming apparatus. Specifically, the first columnar projection 46 and the second columnar projection 55 are each pressed by a lever (not shown) of the drawer unit 90. As a result, the first columnar projection 46 and the second columnar projection 55 each move against the pressing force of the pressing member 93. As a result, as indicated by the dashed arrow in FIG. 15, the casing 10 and the developing roller 30 of the developer cartridge 1 move in the second direction and away from the photosensitive drum 92.

[0130] At this time, the IC chip assembly 60 is fixed in a sandwiched state between the electrical connector 913 and the second guide plate 912. Therefore, even though the casing 10 and the developing roller 30 move in the second direction, the position of the IC chip assembly 60 relative to the drawer unit 90 does not change. In addition, the state of the coil spring 73 also does not change, remaining in the third state. Therefore, the position of the holder 62 relative to the casing 10 in the second direction changes from the standard position (first position) to the separated position (second position). In addition, the boss 621 moves in the second direction inside the through-hole 451.

[0131] In this way, the position of the casing 10 of the developer cartridge 1 in the second direction can be changed without changing the position of the electrical contact surface 611 relative to the drawer unit 90 in the second direction. Therefore, when performing the separation operation, the contact state between the electrical contact surface 611 and the electrical connector 913 can be maintained. Furthermore, even when the image forming apparatus is transported with the developer cartridge 1 attached to the drawer unit 90, the contact state between the electrical contact surface 611 and the electrical connector 913 can be maintained, thereby reducing friction on the electrical contact surface 611.

[0132] <5. Variations> Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. Various modifications will be described below, focusing on the differences from the above embodiment.

[0133] <5-1. First modified example> FIG. 16 is a partially exploded perspective view of a developer cartridge 1A of a first modified example. In the example of FIG. 16, as in the above embodiment, at least a portion of a holder 62A that holds an IC chip 61A is covered by a first cover 45A. However, in the example of FIG. 16, the first cover 45A has bosses 451aA and 451bA. The bosses 451aA and 451bA are aligned in the second direction. The bosses 451aA and 451bA each extend in the third direction from the first cover 45A toward the casing 10A. Meanwhile, the holder 62A has one through-hole 621A that penetrates in the third direction. Both the bosses 451aA and 451bA are inserted into the through-hole 621A.

[0134] The size of through-hole 621A in the second direction is greater than the distance between one edge of boss 451aA in the second direction and the other edge of boss 451bA in the second direction. That is, the size of through-hole 621A in the second direction is greater than the distance between the most distant portions of bosses 451aA and 451bA in the second direction. Therefore, holder 62A can move in the second direction together with through-hole 621A relative to casing 10A and first cover 45A. When holder 62A moves in the second direction, IC chip 61A having electrical contact surface 611A also moves in the second direction together with holder 62A.

[0135] Furthermore, the size of through-hole 621A in the first direction is larger than the size of each of bosses 451aA, 451bA in the first direction. Therefore, holder 62A can move in the first direction together with through-hole 621A relative to casing 10A and first cover 45A. When holder 62A moves in the first direction, IC chip 61A having electrical contact surface 611A also moves in the first direction together with holder 62A. Furthermore, holder 62A may also be movable in a third direction between first cover 45A and first outer surface 11A.

[0136] In this way, by providing the boss 451A on the first cover 45A and the through-hole 621A on the holder 62A, movement of the electrical contact surface 611A in the first and second directions relative to the casing 10A may be realized. Even with this structure, when the casing 10A is tilted in the first direction during installation of the developer cartridge 1A in the drawer unit, the boss 451A can be moved in the first direction inside the through-hole 621A. Furthermore, when a separating operation is performed after installation of the developer cartridge 1A, the boss 451A can be moved in the second direction inside the through-hole 621A. As a result, the position of the casing 10A can be changed while maintaining good contact between the electrical contact surface 611A and the electrical connector.

[0137] The number of bosses 451A provided on first cover 45A may be one or three or more. The number of through holes 621A provided on holder 62A may be two or more. Holder 62A may have a recess into which boss 451A is inserted, instead of through hole 621A. A boss may be provided on the first outer surface of the casing, and the boss of the casing may be inserted into the through hole or recess of the holder. Boss 451A may be a cylinder or a rectangular pillar.

[0138] 17 is a cross-sectional view of the IC chip assembly 60A of FIG. 16 taken along a plane perpendicular to the third direction. As shown in FIG. 17, the holder 62A of this IC chip assembly 60A includes a resin holder member 74A and a leaf spring 75A fixed to the holder member 74A. The holder member 74A has a first end 740A, which is one end of the holder 62A in the first direction. The IC chip 61A is fixed to a holding surface 620A included in the outer surface of the first end 740A. The leaf spring 75A has a second end 750A, which is the other end of the holder 62A in the first direction. In the assembled holder 62A, the first end 740A and the second end 750A are spaced apart in the first direction.

[0139] Leaf spring 75A may be made of, for example, a bent metal plate having flexibility. Leaf spring 75A expands and contracts in a first direction at least between a first state and a second state that is more bent than the first state. The length of leaf spring 75A in the first direction in the first state is longer than the length of leaf spring 75A in the first direction in the second state. Therefore, the distance in the first direction between first end 740A and second end 750A in the first state is longer than the distance in the first direction between first end 740A and second end 750A in the second state. Furthermore, the length of leaf spring 75A in the first direction in at least the second state is shorter than the natural length of leaf spring 75A.

[0140] In this way, by using leaf spring 75A instead of a coil spring, IC chip assembly 60A may be expanded and contracted in the first direction. When developer cartridge 1A is attached to the drawer unit, the electrical contact surface 611A of IC chip 61A can be moved in the first direction relative to casing 10A due to the dimensional difference between boss 451A and through-hole 621A and the expansion and contraction of leaf spring 75A.

[0141] <5-2. Second modified example> FIG. 18 is a partial perspective view of a developer cartridge 1B of a second modified example. In the example of FIG. 18, an electrical contact surface 611B of an IC chip 61B faces the third direction. Therefore, the first direction perpendicular to the electrical contact surface 611B and the third direction are the same. Also, in the example of FIG. 18, a columnar elastic body 63B is provided between the casing 10B and the IC chip assembly 60B. The columnar elastic body 63B may be, for example, a coil spring extending in the first direction. One end of the columnar elastic body 63B in the third direction is fixed to a holder 62B of the IC chip assembly 60B. The other end of the columnar elastic body 63B in the third direction is fixed to a first outer surface of the casing 10B. In other words, the casing 10B and the IC chip assembly 60B are connected by the columnar elastic body 63B.

[0142] 19 and 20 are diagrams showing the movement of the IC chip assembly 60B due to the deformation of the columnar elastic body 63B. As shown in FIG. 19, the columnar elastic body 63B is expandable in a first direction. When the columnar elastic body 63B expands or contracts, the position of the electrical contact surface 611B relative to the casing 10B in the first direction also changes. Furthermore, as shown in FIG. 20, the columnar elastic body 63B is deformable obliquely with respect to the first direction. When the columnar elastic body 63B deforms obliquely, the relative position between one end and the other end of the columnar elastic body 63B changes in a direction perpendicular to the first direction.

[0143] 21 and 22 show the state when the developer cartridge 1B of the second modified example is attached to the drawer unit 90B. As shown in FIGS. 21 and 22, the first cover 45B has a first frame portion 456B and a second frame portion 457B spaced apart in the second direction. The IC chip assembly 60B and the columnar elastic body 63B are housed in a housing portion 452B, which is the space between the first frame portion 456B and the second frame portion 457B. The first cover 45B also has a claw portion 453B that protrudes from the first frame portion 456B toward the housing portion 452B. Before the developer cartridge 1B is attached to the drawer unit 90B, as shown in FIG. 21, a portion of the IC chip assembly 60 contacts the claw portion 453B. This maintains the columnar elastic body 63B in a state compressed in the first direction relative to its natural length.

[0144] When the developer cartridge 1B is attached to the drawer unit 90B, the electrical contact surface 611B of the IC chip 61B comes into contact with the electrical connector 913B, as shown in Fig. 22. At this time, the length of the columnar elastic body 63B in the first direction becomes shorter than in the state shown in Fig. 21. Therefore, the repulsive force of the columnar elastic body 63B maintains the contact state between the electrical contact surface 611B and the electrical connector 913B.

[0145] FIG. 23 shows the state when a separating operation is performed after the developer cartridge 1B is installed. During the separating operation, as shown in FIG. 23, the columnar elastic body 63B deforms obliquely with respect to the first direction. This causes the IC chip assembly 60B connected to one end of the columnar elastic body 63B and the casing 10B connected to the other end of the columnar elastic body 63B to move relative to each other in the second direction. Therefore, the position of the casing 10B in the second direction can be changed without changing the position of the electrical contact surface 611B relative to the drawer unit 90B in the second direction. In other words, the separating operation can be performed while maintaining contact between the electrical contact surface 611B and the electrical connector 913B.

[0146] <5-3.Third modified example> FIG. 24 is a perspective view of a developer cartridge 1C of a third modified example. In the example of FIG. 24, an IC chip assembly 60C includes an IC chip 61C, a holder 62C, a shaft portion 66C, and a lever 67C. The shaft portion 66C extends in the second direction inside the first cover 45C. One end of the shaft portion 66C in the second direction is connected to the holder 62C so as not to rotate relative to the holder 62C. The other end of the shaft portion 66C in the second direction is connected to a lever 67C disposed outside the first cover 45C so as not to rotate relative to the holder 62C. Therefore, when the lever 67C is rotated around the shaft portion 66C as indicated by the dashed arrow in FIG. 24, the shaft portion 66C and the holder 62C also rotate around the shaft portion 66C. This changes the position of the holder 62C in the first direction.

[0147] 25 to 27 are views of the developer cartridge 1C of the third modified example, viewed from one side in the third direction. Before the developer cartridge 1C is attached to the drawer unit, as shown in FIGS. 24 and 25, the IC chip 61C and holder 62C are housed inside the first cover 45C. When the developer cartridge 1C is attached to the drawer unit and the drawer unit is stored in the image forming apparatus, the lever 67C rotates around the shaft portion 66C. This causes a portion of the holder 62C and the IC chip 61C to protrude from the first cover 45C. Then, as shown in FIG. 27, the electrical contact surface 611C of the IC chip 61C comes into contact with an electrical connector 913C provided on the drawer unit.

[0148] The lever 67C may be operated manually by the user after the developer cartridge 1C is installed in the drawer unit. Also, when storing the drawer unit in the main body of the image forming apparatus, the lever 67C may be rotated by a guide surface provided in the main body of the image forming apparatus.

[0149] The first cover 45C has a support surface 454C that contacts the lever 67C before rotation. In the state shown in FIG. 25, one surface of the lever 67C in the second direction contacts the support surface 454C. This allows the lever 67C, shaft portion 66C, holder 62C, and IC chip 61C to be supported in the second direction by the first cover 45C. However, when the lever 67C is rotated as shown in FIG. 26, the lever 67C moves out of the support surface 454C. Therefore, one surface of the lever 67C in the second direction and the support surface 454C are not in contact with each other. Furthermore, the holder 62C is fixed in the position shown in FIG. 26 by a positioning member included in the drawer unit. As a result, the electrical contact surface 611C of the IC chip 61C and the electrical connector 913C are maintained in contact with each other.

[0150] 26, one surface of the holder 62C in the second direction is also out of contact with the first cover 45C. Therefore, the lever 67C, shaft portion 66C, holder 62C, and IC chip 61C can all be moved in the second direction relative to the first cover 45C. Therefore, during the separation operation of the developer cartridge 1C, as shown in FIG. 27, the casing 10C and the first cover 45C can be moved in the second direction while maintaining contact between the electrical contact surface 611C of the IC chip 61C and the electrical connector 913C.

[0151] <5-4. Fourth Variation> Figure 28 is an exploded perspective view of a first cover 45D and an IC chip assembly 60D of a developer cartridge according to a fourth modified example. Figure 29 is a cross-sectional view of the first cover 45D and the IC chip assembly 60D. In the example shown in Figures 28 and 29, an electrical contact surface 611D of the IC chip 61D faces the third direction. Therefore, the first direction perpendicular to the electrical contact surface 611D and the third direction are the same direction.

[0152] 28 and 29, an IC chip assembly 60D of the fourth modification includes an IC chip 61D, a holder 62D that holds the IC chip 61D, and a joint member 63D. The holder 62D has a plurality of claws 622D that extend in the first direction toward the opposite side from the electrical contact surface 611D. In the example of FIG. 28, the holder 62D has four claws 622D. The joint member 63D includes a fixing portion 631D that is fixed to the first cover 45D and an arm 632D that extends in the first direction from the fixing portion 631D toward the holder 62D.

[0153] A spherical portion 633D having a diameter larger than the thickness of the arm 632D is provided at the tip of the arm 632D in the first direction. The spherical portion 633D is held at a position inside the holder 62D by multiple claws 622D. As a result, as shown in FIG. 30, the arm 632D and the holder 62D are connected to each other so as to be rotatable relative to each other. That is, the IC chip 61D and the holder 62D are rotatable relative to each other around the spherical portion 633D. This allows the position of the electrical contact surface 611D of the IC chip 61D relative to the fixed portion 631D to be moved in the second direction. Therefore, during the developer cartridge separation operation, the casing and first cover 45D can be moved in the second direction while maintaining contact between the electrical contact surface 611D of the IC chip 61D and the electrical connector.

[0154] 28 to 30, the claw portion 622D of the holder 62D and the arm 632D of the joint member 63D are relatively movable in the first direction. Therefore, when inserting the developer cartridge into the drawer unit, the IC chip 61D and the holder 62D can be moved in the first direction relative to the fixing portion 631D. This allows the developer cartridge to be inserted while preventing friction on the electrical contact surface 611D of the IC chip 61D.

[0155] Note that an elastic member such as a coil spring that expands and contracts in the first direction may be interposed between fixing portion 631D of joint member 63D and claw portion 622D. Also, an elastic member such as a coil spring that expands and contracts in the first direction may be interposed between first cover 45D and claw portion 622D. In this case, the repulsive force of the elastic member can bring electrical contact surface 611D into better contact with the electrical connector.

[0156] Furthermore, arm 632D may be rotatably connected to fixed portion 631D or first cover 45D. For example, arm 632D may have spherical portions at both ends, one of which may be rotatably held by a plurality of claws provided on first cover 45D. By rotatably connecting both ends of arm 632D in this manner, the position of electrical contact surface 611D in the second direction can be changed more flexibly.

[0157] <5-5. Fifth Variation> FIG. 31 is a partial perspective view of a developer cartridge 1E of a fifth modified example. In the example of FIG. 31, a holder 62E that holds an IC chip 61E is made of a plate-like member that extends in an annular shape and whose ends are connected to each other. The holder 62E is made of, for example, a flexible resin. Therefore, in the example of FIG. 31, the holder 62E itself is an elastic body that can expand and contract in the first direction. This makes it possible to change the distance between both ends of the holder 62E in the first direction. Therefore, when inserting the developer cartridge 1E into the drawer unit, rubbing of the electrical contact surface 611E of the IC chip 61E can be suppressed.

[0158] 31, holder 62E does not need to be made up of multiple members to allow expansion and contraction of holder 62E in the first direction, and holder 62E does not need to use an elastic member in addition to the member that holds IC chip 61E.

[0159] 32 is an exploded perspective view of a first cover 45E and an IC chip assembly 60E according to a fifth modified example. As shown in FIG. 32, the first cover 45E has a boss 451aE extending in a first direction and a boss 451bE extending in the first direction. The bosses 451aE and 451bE are arranged in a second direction. The first cover 45E further has a connecting portion 455E connecting the tips of the bosses 451aE and 451bE.

[0160] Holder 62E extends in an annular shape around boss 451aE and boss 451bE. Claws 623E provided at both ends of holder 62E mesh with each other. This forms a through-hole 621E penetrating in the first direction inside holder 62E. Boss 451aE and boss 451bE are located inside through-hole 621E. Holder 62E also has a plate-shaped portion 624E protruding from its inner circumferential surface toward through-hole 621E. Plate-shaped portion 624E is inserted between boss 451aE and boss 451bE.

[0161] The distance between bosses 451aE and 451bE in the second direction is greater than the thickness of plate-shaped portion 624E in the second direction. Therefore, holder 62E, together with plate-shaped portion 624E, can move in the second direction relative to casing 10E and first cover 45E. When holder 62E moves in the second direction, IC chip 61E, which has electrical contact surface 611E, also moves in the second direction together with holder 62E.

[0162] Furthermore, the size of through-hole 621E in the first direction is larger than the size of each of bosses 451aE, 451bE in the first direction. Therefore, holder 62E can move in the first direction relative to casing 10E and first cover 45E. When holder 62E moves in the first direction, IC chip 61E having electrical contact surface 611E also moves in the first direction together with holder 62E.

[0163] When the developer cartridge 1E is attached to the drawer unit, the holder 62E is sandwiched between the guide plates of the drawer unit, causing the holder 62E to contract in the first direction. Specifically, as the claws 623E provided at both ends of the holder 62E approach each other, a biasing force is generated in a direction in which the claws 623E move apart. Then, with the holder 62E elastically deformed, the electrical contact surface 611E of the IC chip 61E comes into contact with the electrical connector. The biasing force fixes the electrical contact surface 611E and the electrical connector in contact with each other. During a separation operation, the casing 10E moves in the second direction while the electrical contact surface 611E and the electrical connector remain in contact with each other.

[0164] Even with this structure, when the casing 10E is tilted in the first direction during installation of the developer cartridge 1E in the drawer unit, the bosses 451aE, 451bE can be moved in the first direction inside the through-hole 621E. Furthermore, when a separating operation is performed after installation of the developer cartridge 1E, the bosses 451aE, 451bE can be moved in the second direction inside the through-hole 621E. As a result, the position of the casing 10E can be changed while maintaining good contact between the electrical contact surface 611E and the electrical connector.

[0165] The number of bosses provided on the first cover 45E may be one, or may be three or more.

[0166] <5-6. Sixth Variation> Figure 33 is a perspective view of a developer cartridge 1F and drum cartridge 80F of a sixth modified example. The developer cartridge 1F in Figure 33 includes a casing 10F, a developer roller 30F, an IC chip assembly 60F, and a first cover 45F. In the example of Figure 33, the developer cartridge 1F is attached to the drum cartridge 80F rather than to a drawer unit. The drum cartridge 80F has one developer cartridge holder 81F that holds one developer cartridge 1F. A photosensitive drum 82F is provided in the developer cartridge holder 81F. When the developer cartridge 1F is attached to the drum cartridge 80F, the developer roller 30F of the developer cartridge 1F comes into contact with the photosensitive drum 82F.

[0167] 34 is a diagram showing how the drum cartridge 80F with the developer cartridge 1F attached is attached to the image forming apparatus 100F. As shown in FIG. 34, the drum cartridge 80F with the developer cartridge 1F attached is attached to a drum cartridge holding portion 101F provided in the image forming apparatus 100F.

[0168] In this way, a structure equivalent to the IC chip assemblies of the above-described embodiment or the first to fifth modified examples can be employed for a developer cartridge 1F that is mounted in a drum cartridge 80F. Figure 35 is an exploded perspective view of the vicinity of an IC chip assembly 60F of a developer cartridge 1F. As shown in Figure 35, the IC chip assembly 60F of the developer cartridge 1F has an IC chip 61F, which is a storage medium, and a holder 62F that holds the IC chip 61F. The holder 62F is held by a first cover 45F on the side of the casing 10F in the third direction.

[0169] The holder 62F has a first holder member 71F, a second holder member 72F, and a coil spring 73F. The coil spring 73F is an elastic member that expands and contracts in a first direction.

[0170] The first holder member 71F has a boss 621aF, a boss 621bF, and a boss 621cF. The boss 621aF extends in the third direction from a surface of the first holder member 71F facing the first cover 45F toward the first cover 45F. Meanwhile, the first cover 45F has a through-hole 451F. The through-hole 451F penetrates the first cover 45F in the third direction. The boss 621aF is inserted into the through-hole 451aF.

[0171] The bosses 621bF and 621cF each extend in the third direction from the surface of the first holder member 71 facing the casing 10F toward the casing 10F. Meanwhile, the casing 10F has recesses 15aF and 15bF. The recesses 15aF and 15bF are each recessed in the third direction in the first outer surface 11F of the casing 10F. The boss 621bF is inserted into the recess 15aF. The boss 621cF is inserted into the recess 15bF.

[0172] The size (inner dimension) of through-hole 451F in the second direction is larger than the size (outer dimension) of boss 621aF. The size (inner dimension) of recess 15aF in the second direction is larger than the size (outer dimension) of boss 621bF. Furthermore, the size (inner dimension) of recess 15bF in the second direction is larger than the size (outer dimension) of boss 621cF. Therefore, holder 62F, together with bosses 621aF, 621bF, and 621cF, can move in the second direction relative to casing 10F and first cover 45F. When holder 62F moves in the second direction, IC chip 61F having electrical contact surface 611F also moves in the second direction together with holder 62F.

[0173] The size (inner dimension) of through-hole 451F in the first direction is larger than the size (outer dimension) of boss 621aF. The size (inner dimension) of recess 15aF in the first direction is larger than the size (outer dimension) of boss 621bF. The size (inner dimension) of recess 15bF in the first direction is larger than the size (outer dimension) of boss 621cF. Therefore, holder 62F, together with bosses 621aF, 621bF, and 621cF, can move in the first direction relative to casing 10F and first cover 45F. When holder 62F moves in the first direction, IC chip 61F having electrical contact surface 611F also moves in the first direction together with holder 62F.

[0174] 34, the second holder member 72 has a recess 625F. Meanwhile, the drum cartridge 80F has a protrusion 83F. The recess 625F and the protrusion 83F face each other in the first direction. The size of the recess 625F gradually increases as it moves away from the IC chip 61F in the first direction. The size of the protrusion 83F gradually decreases toward the tip in the first direction.

[0175] As shown in FIG. 34, the image forming apparatus 100F has an electrical connector 102F. When the drum cartridge 80F with the developer cartridge 1F attached is inserted into the image forming apparatus 100F, the first holder member 71F comes into contact with components of the image forming apparatus 100F. Furthermore, the protrusion 83F of the drum cartridge 80F fits into the recess 625F of the second holder member 72F. This fixes the position of the second holder member 72F relative to the drum cartridge 80F. As a result, the holder 62F is sandwiched between the components of the image forming apparatus 100F and the drum cartridge 80, causing the coil spring 73F to compress in the first direction. Furthermore, when the drum cartridge F is further inserted into the image forming apparatus 100F, the electrical contact surface 611F of the IC chip 61F comes into contact with the electrical connector 102F.

[0176] The IC chip 61F contacts the electrical connector 102F while receiving the repulsive force of the coil spring 73F. The holder 62F is sandwiched between the electrical connector 102F and the protrusion 83F. This positions the holder 62F relative to the image forming apparatus 100F and the drum cartridge 80F.

[0177] As shown in FIG. 35, the second holder member 72F has claw portions 714F. The claw portions 714F protrude from the second holder member 72F in a direction intersecting the first direction. In the example of FIG. 35, the claw portions 714F protrude from the second holder member 72F in a third direction. Meanwhile, the first holder member 71F has openings 721F. The claw portions 714F are inserted into the openings 721F. This prevents the first holder member 71F from being removed from the second holder 72F.

[0178] The casing 10F of the developer cartridge 1F also has a first rib 46F and a second rib 55F. The first rib 46F protrudes in the third direction from the first outer surface 11F. The second rib 55F protrudes in the third direction from the second outer surface 12F. The drum cartridge 80F also has a first lever 84F and a second lever 85F. During the separation operation, the first lever 84F and the second lever 85F are operated by a driving force from the image forming apparatus. This causes the first rib 46F to be pushed by the first lever 84F. Furthermore, the second rib 55F is pushed by the second lever 85F. This causes the positions of the first rib 46F and the second rib 55F to change. As a result, the casing 10 and the developing roller 30 of the developer cartridge 1 move in the second direction, moving away from the photosensitive drum 92.

[0179] As described above, the position of the holder 62F of this developer cartridge 1F relative to the casing 10F in the second direction can also be changed. Therefore, the position of the casing 10F in the second direction can be changed without changing the position of the electrical contact surface 611F relative to the electrical connector 102F in the second direction. This allows the electrical contact surface 611F and the electrical connector 102F to be separated while maintaining their contact state. As a result, friction on the electrical contact surface 611F can be reduced.

[0180] Also in this developing cartridge 1F, the electrical contact surface 611F can move in the first direction relative to the casing 10F. Therefore, when the drum cartridge 80F is mounted in the image forming apparatus 100F, friction on the electrical contact surface 611F can be suppressed.

[0181] <5-7. Other variations> In the above embodiment, the IC chip having the electrical contact surface is fixed to the outer surface of the holder. However, only the electrical contact surface that contacts the electrical connector may be fixed to the outer surface of the holder, and the portion of the IC chip other than the electrical contact surface may be located elsewhere in the developer cartridge.

[0182] In the above embodiment, the gears in the first gear unit and the second gear unit are engaged with each other by meshing of gear teeth. However, the gears in the first gear unit and the second gear unit may be engaged with each other by friction. For example, a friction member (e.g., rubber) may be provided on the outer periphery of the two gears that engage with each other instead of the gear teeth.

[0183] Furthermore, the developing cartridge 1 in the above embodiment is attached to a drawer unit of an image forming apparatus. However, the developing cartridge of the present invention may be attached to a main body of an image forming apparatus that does not have a drawer unit.

[0184] Furthermore, the detailed shape of the developing cartridge may differ from the shape shown in each drawing of the present application. Furthermore, the elements appearing in the above-described embodiments and modifications may be combined as appropriate within the scope of not causing any contradiction. [Explanation of symbols]

[0185] 1, 1A, 1B, 1C, 1E, 1F Developer Cartridges 10, 10A, 10B, 10C, 10E, 10F Casing 11 First outer surface 12 Second outer surface 13 Developer chamber 14 Openings 20 Agitator 21 Agitator shaft 22 stirring blade 30,30F Developing roller 31 Roller body 32 Roller shaft 40 First Gear Section 41 Coupling 42 Development gear 43 Idle Gear 44 First agitator gear 45, 45A, 45B, 45C, 45D, 45E, 45F First cover 50 Second Gear Section 51 Second agitator gear 52 Detection Gear 53 Conductive materials 54 Second Cover 60, 60A, 60B, 60C, 60D, 60E, 60F IC chip assembly 61, 61A, 61B, 61C, 61D, 61E, 61F IC chip 62, 62A, 62B, 62C, 62D, 62E, 62F holder 63B Columnar Elastic Body 63D Joint material 66C shaft 67C Lever 71, 71F First holder member 72, 72F Second holder member 73,73F Coil spring 74A Holder member 75A leaf spring 80F drum cartridge 81F Developer cartridge holder 82F Photosensitive drum 90,90B Drawer unit 91 Cartridge holder 92 Photosensitive drum 100F Image forming device 101F Drum cartridge holder 102F Electrical Connector 451,451F Through hole 451aA,451bA,451aE,451bE Boss 611, 611A, 611B, 611C, 611D, 611E, 611F Electrical contact surface 620,620A holding surface 621,621F Boss 621A,621E Through hole 631D Fixed part 632D Arm 633D Spherical part 710,740A 1st end 711 First guide surface 712 Second guide surface 713a, 713b Third guide surface 720,750A 2nd end 910 Insertion port 911 First guide plate 912 Second guide plate 913, 913B, 913C Electrical Connectors 914 Guide protrusion

Claims

1. a housing that accommodates a developer therein; a storage medium having an electrical contact surface; a leaf spring deformable in a first direction between a first state and a second state; a developing roller located on one side of the housing in the second direction, the developing roller being rotatable about an axis extending in a third direction different from the first direction and the second direction; a holder that holds the electrical contact surface and is movable in the first direction between a first position and a second position relative to the housing; Equipped with When the leaf spring is in the first state, the holder is located at the first position; When the leaf spring is in the second state, the holder is located at the second position.

2. 2. The developing cartridge according to claim 1, The developing cartridge, wherein the first direction is a direction perpendicular to the electrical contact surface.

3. 3. The developing cartridge according to claim 1, The developing cartridge, wherein the holder is movable together with the storage medium.

4. 4. The developing cartridge according to claim 1, The developing cartridge, wherein the holder holds the storage medium.

5. 5. The developing cartridge according to claim 1, The developing cartridge is characterized in that the holder is located on a side of the housing.

6. A developing cartridge according to any one of claims 1 to 5, The developing cartridge according to claim 1, wherein the length of the leaf spring in the first direction in the first state is longer than the length of the leaf spring in the second state.

Images